Some lovers' presents we cherish—the romantic dinner, the cashmere sweater, the love note. Sexually transmitted diseases (STDs), however, are the mementos we all could do without. Unfortunately, STDs tend to be the gifts that keep on giving as people—often unknowingly—pass them on from person to person. "More than fifteen million new infections occur each year," says Linda Alexander, Ph.D., president and CEO of the American Social Health Association. "But STDs are silent infections. You may not have visible symptoms—especially if you're a woman." Moreover, contrary to popular belief, STD screens are not standard protocol for yearly physicals or gynecological exams. You have to ask your doctor to be tested—which you should do. Early detection is key, as the majority of STDs are treatable and often curable. Most important, they are largely preventable: Use a condom. 


Chlamydia

What it is: A bacterial infection in the genital area.
Symptoms: Vaginal bleeding, unusual discharge from the penis or vagina, abdominal pain, burning during urination, painful intercourse for women or inflammation of the testicles for men. Most people show no visible symptoms; however.
Treatment: Antibiotics will cure it.


Crabs

What it is: Lice in the pubic hair. It can be spread through sexual contact or through bedding, clothing, and toilet seats.
Symptoms: Incredible itching down there.
Treatment: Over-the-counter medications, such as Kwell or A-200, will kill the lice. Pregnant women should use a special product, such as Eurax. All furniture, bedding, and towels that have been exposed to the lice should be washed, dry-cleaned, or vacuumed thoroughly.


Gonorrhea

What it is: A bacterial infection of the genitals.
Symptoms: Burning during urination, green or yellowish vaginal or penile discharge, and for women, abnormal vaginal bleeding and pelvic pain. However, 80 percent of infected women will have no symptoms.
Treatment: Antibiotics will cure it.


Hepatitis B

What it is: A viral infection that affects the liver, hepatitis is spread through exchange of blood, saliva, semen, or vaginal excretions—be it via sexual intercourse, kissing or sharing of contaminated needles.
Symptoms: Hepatitis B can be dangerously asymptomatic, but common signs include fatigue, headache, fever, nausea, loss of appetite, achiness, darkening of the urine and jaundice.
Treatment: Hepatitis B is the only STD for which there is a vaccine. Once contracted, however, there is no treatment. Most cases clear up within two months. Some people remain contagious for the rest of their lives (a test can determine if you are contagious).


Herpes

What it is: A viral infection in the mouth or genital areas.
Symptoms: Herpes Simplex 1 causes cold sores and fever blisters usually in and around the mouth. Herpes Simplex 2 can produce a recurring rash with clusters of red bumps, blisters, or sores, usually on or around the penis, anus, vagina, cervix, buttocks, or thighs. Also, Herpes Simplex 1 can cause genital herpes as well.
Treatment: There's no cure, but recent antiviral medications, such as Valtrex and Fanavir, greatly reduce the frequency and severity of outbreaks.


Human Immunodeficiency Virus (HIV)

What it is: The virus that causes AIDS.
Symptoms: You can be HIV positive for years and show no symptoms. But unexplained weight loss, diarrhea, flu-like symptoms that don't go away, night sweats, persistent fevers, purplish growths on the skin, and constant yeast infections can all point to HIV infection.
Treatment: There is no cure for AIDS. Current drug therapies, known as cocktails, have been successful in keeping HIV from progressing into AIDS for some people, but once AIDS-related illness begins, treatment only keeps diseases (such as cancer or pneumonia) at bay.


Human Papilloma Virus (HPV, or Genital Warts)

What it is: A family of more than 60 kinds of viral infections.
Symptoms: Soft, itchy warts around the penis, vagina, or anus.
Treatment: While the warts can be removed—either with medication or surgery—there is no cure for HPV. Some HPV viruses can cause cervical cancer in women and anal cancer in men and women.


Pelvic Inflammatory Disease (PID)

What it is: A long-term, progressive infection in women that is usually caused by untreated STDs (like chlamydia and gonorrhea). PID can cause permanent damage to a woman's reproductive system.
Symptoms: Unusually long or painful periods; spotting between periods; pain in the lower back or stomach; fever; nausea; vomiting; pain during intercourse.
Treatment: Antibiotics and abstaining from sex until the infection has cleared will cure it. If PID has caused scarring, surgery may be necessary to repair reproductive organs.


Syphilis

What it is: An infection caused by microscopic organisms.
Symptoms: They come in phases, the first of which is sores or ulcers (called chancres) that appear on the genitals or lips and mouth about three to six weeks after infection. The second phase of symptoms may come and go for years and include body rashes—particularly on the palms of the hands or soles of the feet—mild fever; weight loss; and swollen glands. If left untreated, syphilis can cause organ and brain damage and death.
Treatment: If the disease is caught early, it can be cured with antibiotics, but there is no treatment to repair central nervous or organ damage.